We agree that LPC (Linear Predictive Coding), as a fundamental technology, has had a great impact on the research and development of speech-related technologies, including speech analysis, enhancement, coding, recognition and synthesis. LPC technology is based on a framework of mathematics and was first applied to speech signal by Dr. B. S. Atal and Dr. F. Itakura independently . Lots of practical variations and extensions of LPC have been invented and some of them have been applied to proprietary commercial products in individual markets. LSP is one of the inventions based on LPC, but it is special because it has been commonly adopted in digital communications systems (cellular phones and IP phones) and has been used by billions of users around the world. Experts think LSP will be continuously used well into the future. LSP was born and brought up by many researches in the signal processing community. It is worthwhile that great contributions from the community is widely recognized by all users.
 B. S. Atal, “The History of Linear Prediction”, IEEE SIGNAL PROCESSING MAGAZINE, pp. 154-157, MARCH 2006.